Engineering porous structure in Bi-component-active ZnO quantum dots anchored vanadium nitride boosts reaction kinetics for zinc storage

The electrochemical performance of aqueous zinc-ion battery (AZIB) is largely dependent on the fast reaction kinetics, therefore, researchers made a lot of research to improve the ion/electron transfer rate, but did not achieve satisfactory results. Herein, pore engineering is performed by a simple self-sacrificial strategy to obtain bi-component-active ZnO quantum dots (QDs) modified VN nanosheets (ZnO-QDs-VN-0.5) with an interconnected framework. The abundant and evenly distributed porous structure provides a short Zn2+ ion channel for rapid diffusion. Compared to bulk VN-0.5, a unique high-surficial fast electrochemical reaction process is realized by rationally design the electrode. The formed ZnO-QDs-VN-0.5 exhibits a satisfactory specific capacity (384.1 mAh g(-1) at 0.1 A g(-1)), good rate capability and satisfactory cycle life. Moreover, the flexible quasi-solidstate ZnO-QDs-VN-0.5//Zn battery also shows excellent stability, high energy density and power density, which proves that this material can be applied in different fields. The excellent performance may be due to the reasonable adjustment of the multi-phase interface and porous structure control, which significantly promotes the transfer rate of ions of ZnO-QDs-VN-0.5 (D-Zn(2+)approximate to 10(-8) cm(2) s(-1)), and greatly enhances the ion storage sit. In addition, the mechanism of the electrochemical reaction was elucidated by different ex-situ methods. This work provides great hope for the preparation of porous electrode materials and provides a basis for guiding the construction of electrode materials with excellent performance.

Automated summary

By employing a self-sacrificial strategy for pore engineering, a bi-component-active ZnO-QDs-VN-0.5 electrode was designed to optimize ion transfer rate and achieve satisfactory electrochemical performance.